by larger parts i assume your talking about the middle sheet have the rectangular parts nested following the larger curved part instead of being packed into the bottom left corner?

the only way i know of is not automatic you will have to move/rotate them manually. because there is not enough parts to fill that middle sheet its not packing them closer and it appears that you only allowed your parts to rotate 90 degrees when you nested them

make sure you have rotation set for something like 1 degree on that middle sheet and that you used complex nesting when you started the nest